PA-MC-2T3+ Phase-II (T3 subrate)

This feature module describes the availability of clear channel (T3 subrate) on the Two-Port Enhanced Multichannel T3+ Port Adapter (PA-MC-2T3+). It includes information on the benefits of this new feature, supported platforms, configuration examples, and a command reference.

Feature Overview

The PA-MC-2T3+ is a single-width port adapter that provides two T3 interface connections. Each T3 interface can now be independently configured to be either channelized or unchannelized. A channelized T3 provides 28 T1 lines multiplexed into the T3. Each T1 line can be configured into one or more serial interface data channels.

Using the no channelized command, you can configure the T3 as a single, unchannelized serial interface data channel. You can configure this data channel to use all of the T3 bandwidth or a portion of it.

Benefits

The PA-MC-2T3+ now provides the following benefits:

•Two T3 ports each with integrated CSU/DSUs

•Two T3 ports on one single-wide port adapter

•Up to 256 logical, T1 Nx56K and Nx64K channels

•28 T1 ports multiplexed into a single T3 connection

•Channelized T1, fractional T1, and full-rate T1 support

•Subrate and full rate T3 support

•Line and payload loopback capabilities

•Full bit error rate testing on any T1 or any unchannelized T3

•DSX-3 level interface

•Full duplex and connectivity at DS3 rate (44.736 Mbps)

•T3 Scrambling and subrate can be independently or simultaneously enabled in each DSU mode

To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB web site on Cisco Connection Online (CCO) at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

RFCs

•RFC 1406, Definitions of Managed Objects for the DS1 and E1 Interface Types

Configures the PA-MC-2T3+ to emulate a proprietary DSU subrate scheme.

•0—Digital Link or Cisco—300-44210 Kbps

•1—ADC Kentrox T3/E3 IDSU—1500-35000, 44210 Kbps

•2—Larscom Access T45—3100-44210 Kbps

•3—Adtran T3SU 300—75-44210 Kbps

•4—Verilink HDM 2182—1500-44210 Kbps

Default is 0.

Step 6

Router(config-if)# dsu bandwidth bandwidth

Configures the bandwidth for an unchannelized subrate T3 interface.

•bandwidth—a numeric value between 1 and 44210

The default bandwidth is 44210.

Verifying the Configuration

After configuring a new T3 controller, you can verify the configuration by using show commands. To display the status of any a new T3 controller or newly configured interface, complete any of the following tasks in EXEC mode:

Step 1 Display the status of the T3 controller on a Cisco 7200 series router using the show controllers t3 port-adapter/t3-port [brief | tabular] command.

or

Display the status of the T3 controller on a Cisco 7500 series router using the show controllers t3 slot/port-adapter/t3-port [brief | tabular] command:

Router# show controllers t30/1/0brief

T3 0/1/0 is up. Hardware is 2CT3+ single wide port adapter

CT3 H/W Version: 0.1.1, CT3 ROM Version: 0.95, CT3 F/W Version: 2.4.0

FREEDM version: 1, reset 0

Applique type is Subrate T3

No alarms detected.

MDL transmission is disabled

FEAC code received: No code is being received

Framing is C-BIT Parity, Line Code is B3ZS, Clock Source is Line

Rx throttle total 0, equipment customer loopback

Router# show controllers t3 0/1/0 tabular

T3 0/1/0 is up. Hardware is 2CT3+ single wide port adapter

CT3 H/W Version: 0.1.1, CT3 ROM Version: 0.95, CT3 F/W Version: 2.4.0

FREEDM version: 1, reset 0

Applique type is Subrate T3

No alarms detected.

MDL transmission is disabled

FEAC code received: No code is being received

Framing is C-BIT Parity, Line Code is B3ZS, Clock Source is Line

Rx throttle total 0, equipment customer loopback

INTERVAL LCV PCV CCV PES PSES SEFS UAS LES CES CSES

06:17-06:24 0 0 0 0 0 1 0 0 0 0

06:02-06:17 4 2 1 1 0 0 1 0 0 0

05:47-06:02 0 0 0 0 0 0 0 0 0 0

05:32-05:47 0 0 0 0 0 0 0 0 0 0

05:17-05:32 0 0 0 0 0 0 0 0 0 0

05:02-05:17 0 0 0 0 0 0 0 0 0 0

04:47-05:02 0 0 0 0 0 0 0 0 0 0

04:32-04:47 0 0 0 0 0 0 0 0 0 0

04:17-04:32 0 0 0 0 0 0 0 0 0 0

04:02-04:17 0 0 0 0 0 0 0 0 0 0

03:47-04:02 0 0 0 0 0 0 0 0 0 0

03:32-03:47 0 0 0 0 0 0 0 0 0 0

03:17-03:32 0 0 0 0 0 0 0 0 0 0

[additional command output omitted]

Step 2 Display statistics about the serial interface for a specific T3 line on a Cisco 7500 series router using the show interfaces serialslot/port-adapter/t3-port command:

Router# show interfaces serial 1/0/0

Serial1/0/0 is up, line protocol is up

Hardware is cyBus 2CT3+ Serial

MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation HDLC, crc 16, loopback not set

Keepalive set (10 sec)

Last input 00:00:09, output 00:00:07, output hang never

Last clearing of "show interface" counters never

Queueing strategy: fifo

Output queue 0/40, 4 drops; input queue 0/75, 0 drops

5 minute input rate 0 bits/sec, 0 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

4 packets input, 402 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 parity

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 1 abort

5 packets output, 1008 bytes, 0 underruns

0 output errors, 0 applique, 1 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DSU mode 0, bandwidth 44210, scramble 0

or

Use the show interfaces serialport-adapter/t3-port command to display statistics about the serial interface for a specific T3 line on a Cisco 7200 series router:

Router# show interfaces serial 5/0

Serial5/0 is up, line protocol is down

Hardware is PA-MC-2T3+

MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,

reliability 128/255, txload 1/255, rxload 1/255

Encapsulation HDLC, crc 16, loopback not set

Keepalive set (10 sec)

Last input never, output never, output hang never

Last clearing of "show interface" counters never

Queueing strategy: fifo

Output queue 0/40, 0 drops; input queue 0/75, 0 drops

5 minute input rate 0 bits/sec, 0 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

0 packets input, 0 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 parity

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

5823 packets output, 140669 bytes, 0 underruns

0 output errors, 0 applique, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

1 carrier transitions

DSU mode 0, bandwidth 44210, scramble 0

Troubleshooting Tips

Set loopbacks to troubleshoot the PA-MC-2T3+.

Setting Loopbacks

You can configure the T3 controller for loopback modes using the serial interface loopback command. The default is no loopback. The three main loopback modes are: local, network, and remote. The T3 local loopback simultaneously loops the T3 port toward the router and loops the T3 link back toward the network.

The T3 network loopback loops the T3 line or payload back toward the network. A T3 remote loopback loops the T3 line at the remote end. Use T3 loopbacks to diagnose problems with cables between the port adapter and the central switching office at the T3 line level. You can also use the loopback modes with bit error rate (BER) tests.

To set a loopback on the T3 controller or T3 lines, perform the following optional tasks beginning in global configuration mode:

Configuring a Subrate T3 Interface

In order to configure a subrate T3 interface, you must first configure the interface as a full-rate T3 using the no channelized configuration controller command. After the full-rate T3 interface is configured, use the dsu bandwidth command to create a subrate T3 interface.The following example configures a subrate T3 interface on a Cisco 7200 series router:

Router(config)# controller t3 2/0

Router(config-controller# no channelized

Router(config-controller)# exit

Router(config)# interface serial 2/0

Router(config-if)# dsu bandwidth 16000

Router(config-if)# encapsulation frame-relay

Router(config-if)# ip address 10.10.10.10 255.255.255.255

Router(config-if)# no shutdown

Command Reference

This section documents the new command that configures the clear channel T3 subrate feature.

no channelized

To configure the T3 controller for unchannelized mode, use the no channelized configuration controller command. To configure channelized mode, use the channelizedform of this command.

channelized

no channelized

Syntax Description

This command has no arguments or keywords.

Defaults

MTU size is set to 4470.

Command Modes

Configuration controller

Command History

Release

Modification

12.0(14)S

This command was introduced.

Usage Guidelines

Use the no channelized configuration controller command to configure the T3 controller for unchannelized mode. When you configure the PA-MC-2T3+ on a Cisco 7500 series router with the no channelized command, the MTU size is set to 4470. In channelized mode, the default MTU size is 1500. The change in MTU sizes will cause a memory recarve and CBus complex to occur, disrupting all traffic on the router for several minutes.

The following message will be displayed when switching between channelized and unchannelized modes on a Cisco 7500 series router: